--- src/sys/boot/i386/cdboot/Attic/cdboot.S	2004/07/18 16:51:38	1.4
+++ src/sys/boot/i386/cdboot/Attic/cdboot.S	2004/07/18 23:40:07	1.5
@@ -1,72 +1,66 @@
-#
-# Copyright (c) 2001 John Baldwin
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms are freely
-# permitted provided that the above copyright notice and this
-# paragraph and the following disclaimer are duplicated in all
-# such forms.
-#
-# This software is provided "AS IS" and without any express or
-# implied warranties, including, without limitation, the implied
-# warranties of merchantability and fitness for a particular
-# purpose.
-#
-
-# $FreeBSD: src/sys/boot/i386/cdboot/cdboot.s,v 1.9 2001/11/07 01:20:33 jhb Exp $
-# $DragonFly$
-
-#
-# This program is a freestanding boot program to load an a.out binary
-# from a CD-ROM booted with no emulation mode as described by the El
-# Torito standard.  Due to broken BIOSen that do not load the desired
-# number of sectors, we try to fit this in as small a space as possible.
-#
-# Basically, we first create a set of boot arguments to pass to the loaded
-# binary.  Then we attempt to load /boot/loader from the CD we were booted
-# off of. 
-#
-
-#
-# Memory locations.
-#
-		.set MEM_PAGE_SIZE,0x1000	# memory page size, 4k
-		.set MEM_ARG,0x900		# Arguments at start
-		.set MEM_ARG_BTX,0xa100		# Where we move them to so the
-						#  BTX client can see them
-		.set MEM_ARG_SIZE,0x18		# Size of the arguments
-		.set MEM_BTX_ADDRESS,0x9000	# where BTX lives
-		.set MEM_BTX_ENTRY,0x9010	# where BTX starts to execute
-		.set MEM_BTX_OFFSET,MEM_PAGE_SIZE # offset of BTX in the loader
-		.set MEM_BTX_CLIENT,0xa000	# where BTX clients live
-#
-# a.out header fields
-#
+/*
+ * Copyright (c) 2001 John Baldwin
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are freely
+ * permitted provided that the above copyright notice and this
+ * paragraph and the following disclaimer are duplicated in all
+ * such forms.
+ *
+ * This software is provided "AS IS" and without any express or
+ * implied warranties, including, without limitation, the implied
+ * warranties of merchantability and fitness for a particular
+ * purpose.
+ *
+ *
+ * $FreeBSD: src/sys/boot/i386/cdboot/cdboot.s,v 1.9 2001/11/07 01:20:33 jhb Exp $
+ * $DragonFly$
+ */
+
+/*
+ * This program is a freestanding boot program to load an a.out binary
+ * from a CD-ROM booted with no emulation mode as described by the El
+ * Torito standard.  Due to broken BIOSen that do not load the desired
+ * number of sectors, we try to fit this in as small a space as possible.
+ *
+ * Basically, we first create a set of boot arguments to pass to the loaded
+ * binary.  Then we attempt to load /boot/loader from the CD we were booted
+ * off of. 
+ */
+
+#include "../bootasm.h"
+
+		/*
+		 * a.out header fields
+		 */
 		.set AOUT_TEXT,0x04		# text segment size
 		.set AOUT_DATA,0x08		# data segment size
-		.set AOUT_BSS,0x0c		# zero'd BSS size
+		.set AOUT_BSS,0x0c		# zerod BSS size
 		.set AOUT_SYMBOLS,0x10		# symbol table
 		.set AOUT_ENTRY,0x14		# entry point
 		.set AOUT_HEADER,MEM_PAGE_SIZE	# size of the a.out header
-#
-# Flags for kargs->bootflags
-#
+
+		/*
+		 * Flags for kargs->bootflags
+		 */
 		.set KARGS_FLAGS_CD,0x1		# flag to indicate booting from
 						#  CD loader
-#
-# Segment selectors.
-#
+		/*
+		 * Segment selectors.
+		 */
 		.set SEL_SDATA,0x8		# Supervisor data
 		.set SEL_RDATA,0x10		# Real mode data
 		.set SEL_SCODE,0x18		# PM-32 code
 		.set SEL_SCODE16,0x20		# PM-16 code
-#
-# BTX constants
-#
+
+		/*
+		 * BTX constants
+		 */
 		.set INT_SYS,0x30		# BTX syscall interrupt
-#
-# Constants for reading from the CD.
-#
+
+		/*
+		 * Constants for reading from the CD.
+		 */
 		.set ERROR_TIMEOUT,0x80		# BIOS timeout on read
 		.set NUM_RETRIES,3		# Num times to retry
 		.set SECTOR_SIZE,0x800		# size of a sector
@@ -87,16 +81,17 @@
 		.set DIR_SIZE,10		# Offset of 64-bit length
 		.set DIR_NAMELEN,32		# Offset of 8-bit name len
 		.set DIR_NAME,33		# Offset of dir name
-#
-# We expect to be loaded by the BIOS at 0x7c00 (standard boot loader entry
-# point)
-#
+
+		/*
+		 * Program start.
+		 *
+		 * We expect to be loaded by the BIOS at 0x7c00 (standard
+		 * boot loader entry point)
+		 */
 		.code16
 		.globl start
 		.org 0x0, 0x0
-#
-# Program start.
-#
+
 start:		cld				# string ops inc
 		xor %ax,%ax			# zero %ax
 		mov %ax,%ss			# setup the
@@ -106,9 +101,11 @@ start:		cld				# string ops inc
 		mov %dl,drive			# Save BIOS boot device
 		mov $msg_welcome,%si		# %ds:(%si) -> welcome message
 		call putstr			# display the welcome message
-#
-# Setup the arguments that the loader is expecting from boot[12]
-#
+
+		/*
+		 * Setup the arguments that the loader is expecting from
+		 * boot[12]
+		 */
 		mov $msg_bootinfo,%si		# %ds:(%si) -> boot args message
 		call putstr			# display the message
 		mov $MEM_ARG,%bx		# %ds:(%bx) -> boot args
@@ -122,9 +119,9 @@ start:		cld				# string ops inc
 		mov %dl,0x4(%bx)		#  in kargs->bootdev
 		or $KARGS_FLAGS_CD,0x8(%bx)	# kargs->bootflags |=
 						#  KARGS_FLAGS_CD
-#
-# Load Volume Descriptor
-#
+		/*
+		 * Load Volume Descriptor
+		 */
 		mov $VOLDESC_LBA,%eax		# Set LBA of first VD
 load_vd:
 		mov $1,%dh			# One sector
@@ -138,15 +135,18 @@ load_vd:
 		mov $msg_novd,%si		# No VD
 		jmp error			# Halt
 have_vd:					# Have Primary VD
-#
-# Lookup the loader binary.
-#
+
+		/*
+		 * Lookup the loader binary.
+		 */
 		mov $loader_path,%si		# File to lookup
 		call lookup			# Try to find it
-#
-# Load the binary into the buffer.  Due to real mode addressing limitations
-# we have to read it in in 64k chunks.
-#
+
+		/*
+		 * Load the binary into the buffer.  Due to real mode
+		 * addressing limitations we have to read it in in 64k
+		 * chunks.
+		 */
 		mov DIR_SIZE(%bx),%eax		# Read file length
 		add $SECTOR_SIZE-1,%eax		# Convert length to sectors
 		shr $11,%eax
@@ -171,13 +171,15 @@ load_notrunc:	sub %dh,%cl			# Update cou
 		jcxz load_done			# Done?
 		jmp load_loop			# Keep going
 load_done:
-#
-# Turn on the A20 address line
-#
+		/*
+		 * Turn on the A20 address line.
+		 */
 		call seta20			# Turn A20 on
-#
-# Relocate the loader and BTX using a very lazy protected mode
-#
+
+		/*
+		 * Relocate the loader and BTX using a very lazy
+		 * protected mode.
+		 */
 		mov $msg_relocate,%si		# Display the
 		call putstr			#  relocation message
 		mov MEM_READ_BUFFER+AOUT_ENTRY,%edi # %edi is the destination
@@ -212,8 +214,8 @@ pm_start:	mov $SEL_SDATA,%ax		# Initiali
 		rep				# zero the
 		stosl				#  bss
 		mov MEM_READ_BUFFER+AOUT_ENTRY,%esi # %esi -> relocated loader
-		add $MEM_BTX_OFFSET,%esi	# %esi -> BTX in the loader
-		mov $MEM_BTX_ADDRESS,%edi	# %edi -> where BTX needs to go
+		add $MEM_BTX_LDR_OFF,%esi	# %esi -> BTX in the loader
+		mov $MEM_BTX_ORG,%edi	# %edi -> where BTX needs to go
 		movzwl 0xa(%esi),%ecx		# %ecx -> length of BTX
 		rep				# Relocate
 		movsb				#  BTX
@@ -228,44 +230,50 @@ pm_16:		mov $SEL_RDATA,%ax		# Initialize
 		ljmp $0,$pm_end			# Long jump to clear the
 						#  instruction pre-fetch queue
 pm_end:		sti				# Turn interrupts back on now
-#
-# Copy the BTX client to MEM_BTX_CLIENT
-#
+
+		/*
+		 * Copy the BTX client to MEM_BTX_USR.
+		 */
 		xor %ax,%ax			# zero %ax and set
 		mov %ax,%ds			#  %ds and %es
 		mov %ax,%es			#  to segment 0
-		mov $MEM_BTX_CLIENT,%di		# Prepare to relocate
+		mov $MEM_BTX_USR,%di		# Prepare to relocate
 		mov $btx_client,%si		#  the simple btx client
 		mov $(btx_client_end-btx_client),%cx # length of btx client
 		rep				# Relocate the
 		movsb				#  simple BTX client
-#
-# Copy the boot[12] args to where the BTX client can see them
-#
+
+		/*
+		 * Copy the boot[12] args to where the BTX client
+		 * can see them.
+		 */
 		mov $MEM_ARG,%si		# where the args are at now
-		mov $MEM_ARG_BTX,%di		# where the args are moving to
+		mov $MEM_BTX_USR_ARG,%di		# where the args are moving to
 		mov $(MEM_ARG_SIZE/4),%cx	# size of the arguments in longs
 		rep				# Relocate
 		movsl				#  the words
-#
-# Save the entry point so the client can get to it later on
-#
+
+		/*
+		 * Save the entry point so the client can get to it
+		 * later on
+		 */
 		pop %eax			# Restore saved entry point
 		stosl				#  and add it to the end of
 						#  the arguments
-#
-# Now we just start up BTX and let it do the rest
-#
+		/*
+		 * Now we just start up BTX and let it do the rest
+		 */
 		mov $msg_jump,%si		# Display the
 		call putstr			#  jump message
 		ljmp $0,$MEM_BTX_ENTRY		# Jump to the BTX entry point
 
-#
-# Lookup the file in the path at [SI] from the root directory.
-#
-# Trashes: All but BX
-# Returns: BX = pointer to record
-#
+		/*
+		 * Lookup the file in the path at [SI] from the root 
+		 * directory.
+		 *
+		 * Trashes: All but BX
+		 * Returns: BX = pointer to record
+		 */
 lookup:		mov $VD_ROOTDIR+MEM_VOLDESC,%bx	# Root directory record
 		push %si
 		mov $msg_lookup,%si		# Display lookup message
@@ -290,13 +298,17 @@ lookup_done:	mov $msg_lookupok,%si		# Su
 		call putstr
 		ret
 
-#
-# Lookup file at [SI] in directory whose record is at [BX].
-#
-# Trashes: All but returns
-# Returns: CF = 0 (success), BX = pointer to record, SX = next path item
-#          CF = 1 (not found), SI = preserved
-#
+		/*
+		 * Lookup file at [SI] in directory whose record is at [BX].
+		 *
+		 * Trashes: All but returns
+		 *
+		 * Returns:	CF = 0 (success)
+		 *		BX = pointer to record,
+		 *		SX = next path item
+		 *		CF = 1 (not found)
+		 *		SI = preserved
+		 */
 find_file:	mov DIR_EXTENT(%bx),%eax	# Load extent
 		xor %edx,%edx
 		mov DIR_EA_LEN(%bx),%dl
@@ -371,11 +383,12 @@ ff.match:	add $2,%sp			# Discard saved %
 		clc				# Clear carry
 		ret
 
-# Load DH sectors starting at LBA EAX into [EBX].  No registers are destroyed.
-# Don't trust the BIOS, especially with regards to the msb 16 bits of our
-# registers.
-#
-read:		pushal				# don't screw around
+		/*
+		 * Load DH sectors starting at LBA EAX into [EBX].  No
+		 * registers are destroyed.  Don't trust the BIOS, especially
+		 * with regards to the msb 16 bits of our registers.
+		 */
+read:		pushal				# dont screw around
 		mov %eax,edd_lba		# LBA to read from
 		mov %ebx,%eax			# Convert address
 		shr $4,%eax			#  to segment
@@ -398,18 +411,18 @@ read.error:	mov %ah,%al			# Save error
 		call hex8			#  as hex
 		mov $msg_badread,%si		# Display Read error message
 
-#
-# Display error message at [SI] and halt.
-#
+		/*
+		 * Display error message at [SI] and halt.
+		 */
 error:		call putstr			# Display message
 halt:		hlt
 		jmp halt			# Spin
 
-#
-# Display a null-terminated string.
-#
-# Trashes: AX, SI
-#
+		/*
+		 * Display a null-terminated string.
+		 *
+		 * Trashes: AX, SI
+		 */
 putstr:
 putstr.load:	lodsb				# load %al from %ds:(%si)
 		test %al,%al			# stop at null
@@ -418,8 +431,10 @@ putstr.load:	lodsb				# load %al from %d
 putstr.putc:	call putc			# output char
 		jmp putstr.load			# next char
 
-# Display a single char(%al).  Don't trust the bios to save our regs.
-#
+		/*
+		 * Display a single char(%al).  Don't trust the bios to save
+		 * our regs.
+		 */
 putc:		pushal
 		mov $0x7,%bx			# attribute for output
 		mov $0xe,%ah			# BIOS: put_char
@@ -427,9 +442,9 @@ putc:		pushal
 		popal
 		ret				# Return to caller
 
-#
-# Output the "twiddle"
-#
+		/*
+		 * Output the "twiddle"
+		 */
 twiddle:	push %ax			# Save
 		push %bx			# Save
 		mov twiddle_index,%al		# Load index
@@ -445,9 +460,9 @@ twiddle:	push %ax			# Save
 		pop %ax				# Restore
 		ret
 
-#
-# Enable A20
-#
+		/*
+		 * Enable A20
+		 */
 seta20: 	cli				# Disable interrupts
 seta20.1:	in $0x64,%al			# Get status
 		test $0x2,%al			# Busy?
@@ -462,9 +477,9 @@ seta20.2:	in $0x64,%al			# Get status
 		sti				# Enable interrupts
 		ret				# To caller
 
-#
-# Convert AL to hex, saving the result to [EDI].
-#
+		/*
+		 * Convert AL to hex, saving the result to [EDI].
+		 */
 hex8:		pushl %eax			# Save
 		shrb $0x4,%al			# Do upper
 		call hex8.1			#  4
@@ -477,11 +492,11 @@ hex8.1: 	andb $0xf,%al			# Get lower 4
 		stosb				# Save char
 		ret				# (Recursive)
 
-#
-# BTX client to start btxldr
-#
+		/*
+		 * BTX client to start btxldr
+		 */
 		.code32
-btx_client:	mov $(MEM_ARG_BTX-MEM_BTX_CLIENT+MEM_ARG_SIZE-4), %esi
+btx_client:	mov $(MEM_BTX_USR_ARG-MEM_BTX_USR+MEM_ARG_SIZE-4), %esi
 						# %ds:(%esi) -> end
 						#  of boot[12] args
 		mov $(MEM_ARG_SIZE/4),%ecx	# Number of words to push
@@ -490,32 +505,35 @@ push_arg:	lodsl				# Read argument
 		push %eax			# Push it onto the stack
 		loop push_arg			# Push all of the arguments
 		cld				# In case anyone depends on this
-		pushl MEM_ARG_BTX-MEM_BTX_CLIENT+MEM_ARG_SIZE # Entry point of
+		pushl MEM_BTX_USR_ARG-MEM_BTX_USR+MEM_ARG_SIZE # Entry point of
 						#  the loader
 		push %eax			# Emulate a near call
-		mov $0x1,%eax			# 'exec' system call
+		mov $0x1,%eax			# "exec" system call
 		int $INT_SYS			# BTX system call
 btx_client_end:
 		.code16
 
 		.p2align 4
-#
-# Global descriptor table.
-#
+
+		/*
+		 * Global descriptor table.
+		 */
 gdt:		.word 0x0,0x0,0x0,0x0		# Null entry
 		.word 0xffff,0x0,0x9200,0xcf	# SEL_SDATA
 		.word 0xffff,0x0,0x9200,0x0	# SEL_RDATA
 		.word 0xffff,0x0,0x9a00,0xcf	# SEL_SCODE (32-bit)
 		.word 0xffff,0x0,0x9a00,0x8f	# SEL_SCODE16 (16-bit)
 gdt.1:
-#
-# Pseudo-descriptors.
-#
+
+		/*
+		 * Pseudo-descriptors.
+		 */
 gdtdesc:	.word gdt.1-gdt-1		# Limit
 		.long gdt			# Base
-#
-# EDD Packet
-#
+
+		/*
+		 * EDD Packet
+		 */
 edd_packet:	.byte 0x10			# Length
 		.byte 0				# Reserved
 edd_len:	.byte 0x0			# Num to read
@@ -525,9 +543,9 @@ edd_lba:	.quad 0x0			# LBA
 
 drive:		.byte 0
 
-#
-# State for searching dir
-#
+		/*
+		 * State for searching dir
+		 */
 rec_lba:	.long 0x0			# LBA (adjusted for EA)
 rec_size:	.long 0x0			# File size
 name_len:	.byte 0x0			# Length of current name